Usage of sugar meter
Handheld/portable sugar meters are mainly used for convenient and rapid determination of the refractive index of sugar solutions. It has the characteristics of easy portability and convenient handheld use. This instrument is widely used in the beverage, food, sugar making, and alcohol industries.
1, The working principle of a sugar meter
When light enters another medium from one medium, it undergoes refraction, and the ratio of the incident angle sine is constant, which is called the refractive index. The content of soluble solids in fruit and vegetable juice is directly proportional to the refractive index under certain conditions (at the same temperature and pressure). Therefore, measuring the refractive index of fruit and vegetable juice can determine the concentration (sugar content) of the juice. The commonly used instrument is a handheld refractometer, also known as a sugar mirror or handheld sugar meter. By measuring the soluble solid content (sugar content) of fruits and vegetables, the quality of fruits and vegetables can be understood, and the maturity of fruits can be estimated approximately. Handheld sugar meters are generally cylindrical in shape.
2, Instructions for using handheld sugar refractometer
(1) Instrument structure
① , Refractive Prism ②, Cover Plate ③, Calibration Bolt ④, Optical System Pipeline ⑤, Eyepiece (Sight Adjustment Ring)
(2) Usage
Open the cover plate ② and carefully wipe off the inspection prism ① with a soft cloth. Take a few drops of the solution to be tested and place them on the testing prism. Gently close the cover to avoid the formation of bubbles and spread the solution all over the surface of the prism. Align the instrument's light plate with the light source or bright spot, observe the field of view through the eyepiece, rotate the eyepiece to adjust the handwheel ⑤, and make the blue and white boundary of the field of view clear. The scale value of the boundary line is the concentration of the solution.
(3) Correction and temperature correction
The instrument needs to calibrate the zero point before measurement. Take a few drops of distilled water and place them on the detection prism. Turn the zero adjustment screw ③ to adjust the dividing line to the 0% mark position. Then clean the inspection prism and perform the inspection. Some models of instruments require the preparation of standard solution to replace distilled water during calibration.
Another method is (only suitable for measuring sugar content): use a temperature correction table to add (or subtract) the temperature correction value read at ambient temperature to obtain accurate values.
(4) Precautions
The instrument is a precision optical instrument, and the following precautions should be taken during use and maintenance:
1. It is necessary to be careful and cautious during use, strictly follow the instructions, and do not loosen the connection parts of the instrument at will. It is not allowed to fall or collide, and violent vibration is strictly prohibited.
2. After use, it is strictly prohibited to directly put it into water for cleaning. It should be wiped with a clean soft cloth. The optical surface should not be bumped or scratched.
3. The instrument should be stored in a dry and corrosion-free place.
4. Avoid losing spare parts.
